Indicia registration method and apparatus



March 26, 1968 I J. A. HAMILTON 3,374,602

INDICIA REGISTRATION METHOD AND APPARATUS 3 sheets sheet l s I I II I INTERMITTENT INDEXING IN VE NTOR.

: JYJeZ J1. Hamzllfow ATTORNEYS March 26, 1968 J. A. HAMILTON 3,374,602

INDICIA REGISTRATION METHOD AND APPARATUS Filed Aug. 18, 1965 3 Sheets-Sheet 2 36 FEEDING FEEDING DRAW ROLLS l6 8 cLosEb----- CAM-SWITCH 38 p 73 73 PHOTOCELL T] TI SIGNAL V D DANGER ROLL l8 POSITION 62 64 WW I 74 4 38 6 CLUTCH PHOTOOELL 54 /30 U K I T 22 BRAKE Q 46 I8 fi 24 CLUTCH a BRAKE POWER SUPPLY J 58 4Z{ m I 1 March 26, 1968 J. A. HAMILTON 3,374,602

INDICIA REGISTRATION METHOD AND APPARATUS Filed Aug. 18, 1965 3 Sheets-Sheet 5 United States Patent 3,374,602 INDICIA REGISTRATION METHOD AND APPARATUS Joel A. Hamilton, Clifton, N.J., assignor to Mahaify & Harder Engineering Co., Totowa, NJ. Filed Aug. 18, 1965, Ser. No. 480,739 14 Claims. (Cl. 53-51) ABSTRACT OF THE DISCLOSURE It is difiicult to apply a web of cover material that has units of printed matter repeated at uniform points along its length to a series of trays as they index on a packaging line, so that each unit of printed matter on the web is aligned with a tray. To achieve the desired alignment between tray and cover, the apparatus and method of this patent use a web of cover material on which the length of the units or repeats of printed matter is slightly less than the length of a tray. The cover web is fed to the trays in increments of one repeat of the printed matter as the trays index. Continued movement of the trays for a short period after feeding of the web has stopped, stretches the increment of web so that it is as long as a tray, thereby aligning the printed matter on the web with the tray.

This invention relates to registration of indicia. More particularly, this invention relates to methods and apparatus for applying a continuous web of material to a corresponding series of receiving elements in such a manner that printed indicia on the web are maintained in registry with respective receiving elements.

In a preferred embodiment of the invention to be described hereinbelow, the receiving elements comprise package-forming dies mounted for movement sequentially past a series of packaging stations. These dies are arranged to receive a film of flexible sheet material drawn from a supply roll and adapted to be formed into packages containing products such as luncheon meat or the like. Frequently it is desired to apply printed indicia to such packages. This can be done by pre-printing the roll stock with a repetitive series of displays presenting the desired information, and arranging that each display is placed in registry with a corresponding die as the packages are being formed. One problem with this approach is that the longitudinal spacing between the individual displays on the roll stock will not ordinarily be precisely the same as the spacing between the package-forming dies, due to manufacturing tolerances, humidity and temperature effects, etc., and thus special arrangements must be made to obtain the desired registration.

In some packaging machines, this problem has been resolved in accordance with well known concepts, e.g. as taught in US. Patent 2,375,451. In such machines, the indicia is printed with a longitudinal spacing slightly less than the spacing between the package-forming dies, and the film is controllably stretched as it is being applied to the dies so as to maintain the indicia substantially in registry with the dies.

One of the practical difficulties presented by machines of this type is that excessive stress may be developed in the film where it is attached to the dies, thus tending to pull the film away from the die and cause undesirable wrinkling or even tearing of the plastic packaging material. This difiiculty becomes particularly acute in packaging machines where the dies are moved intermittently. One solution to the problem for such intermittent motion machines is shown in US. Patent 3,126,431, issued on Mar. 24, 1964, to John R. Harder et al, In accordance with the disclosure of that patent, the film of flexible pack- 3,374,602 Patented Mar. 26, 1968 aging material is controllably pre-stretched independently of the packaging dies, and thereafter applied to the dies under reduced tension just suflicient to maintain the desired amount of stretch.

Although the techniques disclosed in the aforementioned US. Patent 3,164,831 are effective in general to produce the desired results, there is a need for improved registration apparatus and methods. For example, it is desirable to provide fully reliable and precise registration equipment which is more economical to manufacture and thus usable more universally. Accordingly, it is one object of this invention to provide registration apparatus which is superior to that available heretofore. A more specific object of this invention is to provide simplified apparatus and methods for registering indicia on a printed web with corresponding receiving elements. Other objects, aspects and advantages of the present invention will in part be pointed out in, and in part apparent from, the following description of a preferred embodiment of the invention, considered together with the accompanying drawings in which:

FIGURE 1 is a perspective view of the pertinent por tions of a packaging machine incorporating the present invention;

FIGURE 2 is a timing diagram presenting the relationship between certain functions carried out by the machine of FIGURE 1;

FIGURE 3 is a circuit diagram showing the electrical interconnections of the operative controls; and

FIGURES 4-7 are sequential views of the film-feeding mechanism at different times during an operating cycle, the respective times being indicated by corresponding reference numerals on the timing diagram of FIGURE 2.

Referring now to FIGURE 1, there is shown a packaging machine comprising a series of dies in the form of trays 10 which are driven with an intermittent indexing movement (by side chains 11a and associated intermittent drive means 11b) around a closed path having a generally oval configuration. Apparatus of this character already is basically disclosed in prior US. Patents 3,061,- 984, 3,126,431, 3,125,839, and 3,180,066. In order to simplify the disclosure herein, therefore, only those parts necessary to an understanding of the present invention are illustrated herein; for further detailed information on the design and operation of the basic portions of the packaging apparatus, reference should be made to the previously identified patents.

To the left in FIGURE 1 is a supply roll 12 comprising a sheet of flexible packaging film 14. This film extends to the right to a set of three draw rolls 16, the lower two 16a and 16b of which are power-driven in synchronisrn, and the upper central roll of which is an idler in pressure contact with the two lower rolls. The film 14 is wound around the draw rolls 16 and extends upwardly to pass over a dancer roll 18 and thence downwardly to a lay down roll 20 which guides the film into position where it is secured to the trays 1i Dancer roll 18 is supported at its ends by a pair of arms 22 (only of which is shown) pivoted at 24 to accommodate vertical motion of the dancer roll as the trays are being indexed.

Power for the draw rolls 16a and 16b is supplied by a chain 26 driven at constant speed by the main drive motor for the packaging machine (not shown). This power is controlled by a magnetically-operated clutch 28 of conventional construction. Over-travel of the draw rolls is prevented by an electrically-operated brake 30 also of conventional construction and energized whenever the clutch 28 is deactivated.

Positioned above the trays 1G is a vertically-reciprocable packaging head 32. As shown in the aforementioned Patent 3,061,984, and in copending application Ser. No.

368,925 filed May 20, 1964 (see particularly the element identified with reference character 36), the packaging 'trays. The first station serves to make a preliminary seal of the film 14 to the peripheral edges of corresponding cup-shaped package portions held in the side-by-side cavities of the trays 10. At the second station, each partiallycompleted container is evacuated and a final seal is made of the aperture through which the package was evacuated.

The film 14 carries printed indicia, illustrated herein as small marks 34 placed at uniformly spaced positions along the film. Of course, the printed material on the film normally would be considerably more extensive, and the disclosure in this regard has been simplified merely for purposes of clarity. It will be understood, that the spacing between the marks 34 on the film 14 as it leaves the supply roll 12 is slightly less than the spacing between the trays 10, e.g. a mark spacing of 7 and a tray spacing of 5 /4". Thus, it is necessary that the film be stretched in order to obtain proper registry between the printing and the trays. This stretching of the film is effected in the novel manner now to be described.

Referring to the timing diagram of FIGURE 2, the indexing motion of the trays starts at a time identified by vertical line 36. At this'time the draw rolls 16 are stopped, as indicated by curve A, and the operative parts .are positioned as shown in solid outline in FIGURE 4. Shortly after the indexing motion begins, a switch 38 (FIGURE 2, curveB; also see FIGURE 3) is closed by a cam 40 rotated at constant speed by the main drive motor for the packaging machine. This cam rotates once for each complete cycle of the packaging machine.

Closure of switch 38 completes an energizing circuit from the A-C power mains 42 to a draw roll relay generally indicated at 44. This circuit passes through a' normally-closed switch 46 adapted to be operated by the dancer roll arm 22 under certain conditions as will be explained hereinbelow. When the relay 44 pulls in, it completes a lock-up circuit through its contacts 48and contacts 50 of a photocell relay generally indicated at 52. Simultaneously, contacts 54 of relay 44 open to deenergize the brake 30, and contacts 56 close to energize the clutch '28. The energizing current for the brake and clutch is furnished by a power supply generally indicated at 58 and connected to the A-C power mains 42.

When the clutch 28 is engaged and brake 30 deenergized, the draw rolls 16 start feeding the film 14 at constant speed to the dancer roll 18. The position of the operative parts at this time is shown in FIGURE 5. Thereafter, the downward motion of the dancer roll is slowed, but the roll continues to move down because the indexing movement of the trays 10 at this part of the a downward motion of the dancer roll, as indicated by the horizontal portion 62 of curve D in FIGURE 2. The trays 10, however, continue to move and therefore stretch the film 14 between the draw rolls 1 6 and the tray 10 to which the film then is effectively attached.

The indexing motion of the trays 10 follows a speed pattern consisting of an initial acceleration up to a relatively high speed followed by a terminal decelaration to the next rest position. A typical tray indexing curve is shown in FIGURE 19 in the aforementioned Patent 3,180,066. Near the end of the indexing movement, the speed of the trays 10 drops below the feed rate of the draw rolls 16, and at that point the dancer roll 18 lifts up from the stop 60. This is illustrated by the rising portion 64 of curve D, FIGURE 2. Accordingly, for a short period just before the end of the tray indexing motion the stress on the film 14 between the draw rolls 16 and the trays 10 is reduced to the very slight tension of the dancer roll spring (not shown, but illustrated in the aforementioned US. Patent 3,126,431).

After the trays come to rest, draw rolls 16 continue to feed the film 14 to the dancer roll 18 and this roll accordingly rises at, a constant rate as indicated 'by the portion 66 of curve D, FIGURE 2. Towards the end of the rest period of the tray motion cycle, the cam switch 38 is opened (curve B) but the relay 44 remains energized due to the lock-up circuit through its contacts 48.

Shortly thereafter, one of the 'eyemarks 34 will pass between a light source 70 (FIGURES 1 and 3) and a photocell 72, thereby causing a signal to be sent to a photocell sensing unit 74. This unit responds to such signal by energizing the photocell relay 52, thus interrupting the lock-up circuit for relay 44. The latter relay drops out to deactivate clutch 28 and energize brake 30.

Consequently, the draw rolls 16 stop and the feeding of film 14 is arrested.

The complete cycle then repeats, with the trays 10 starting their indexing movement at the time indicated by line 36a in FIGURE 2. The dancer roll'18 again is drawn down, and the cam switch 38 is activated to commence feeding the film 14 to the draw rolls. Near the end of the indexing cycle, the dancer strikes stop 60 and the continuing tray movement stretches the film a small amount under substantial tension. Before the trays stop, the stress in the film is relaxed by the continued feeding of the film 14 because the rate of tray movement drops below the draw roll feed rate. Ultimately, the draw rolls stop when the next mark 34 reaches photocell 72 to produce a signal 73 for unit 74.

Since the draw rolls 16 are stopped once each machine cycle by the arrival of one of the marks 34 in front of photocell 72, it will be evident that for each cycle, the draw rolls feed to the trays 10 an exactly metered portion of film 14 equal to the spacing between the marks. The distance between these marks in the horizontal region of the film 14, i.e., prior to the draw rolls 16, is less than the spacing between the trays 10, but beyond the draw rolls the film 14 is stretched, while the 'draw roll arm 22 is arrested by stop 60, to cause each exactly metered portion of the film to match precisely the longitudinal spacing between the trays. The only adjustment that need 7 descends into operating position to heat-seal the film 14.

Thus the film in the preliminary seal station is not highly stressed at the time the heated seal bars make contact, and this tends to minimize the development of wrinkles and other faults in the plastic film.

It appears that the stretching of the film causes a permanent deformation of the plastic material, i.e., a deformation beyond the yield point, or at least a deformation of such magnitude that substantial time would be required for the film to return towards its original condition any significant amount. due to internal memory tion, thus making it unnecessary to provide expensive servo arrangements for detecting and correcting small errors, eg as by on-oif control means for incrementally increasing or decreasing the amount of stretch applied in accordance with a detected error signal.

The system herein also is advantageous because it can readily be converted to non-registration operation simply by turning off the photocell unit 74. In that event, relay 52 remains deenergized, and the upward movement of the dancer roll 18 will continue until arm 22 operates switch 46, thereby deenergizing relay 44 and stopping the draw rolls 16. The machine then operates conventionally. That is, the dancer roll is pulled down when the indexing motion starts, thus closing switch 46 and preparing the energizing circuit for switch 38 to activate relay 44 at the predetermined point in the cycle. Since the dancer roll 18 started at a higher position than when the registration system was in operation, the tray indexing cycle is completed with the dancer still above the stop 60. Accordingly, the film 14 is not stretched. During the rest portion of the cycle, the continuing feed of the draw rolls 16 causes the dancer to elevate to its highest position engaging the switch 46 and stopping the film feed. Thus, the film feeding equipment automatically provides the required amount of unstretched film, according to the demand of the machine.

The system will also automatically return to registration operation if the photocell system is reactivated. This return may require several machine cycles. During the first cycle, the downstroke of the dancer 18 will be the same as though the registration system were not activated, but on the upstroke the dancer will stop when the next eye mark 34 is sensed. Ordinarily, this will occur before the dancer reaches its top position. Thus, on the next downstroke, the dancer will go to a lower position, because the draw rolls 16 have fed to the dancer an amount of film slightly less than the amount drawn by the trays. On the next cycle the dancer will go .to a still lower position and, in this way, through several cycles, the dancer will ultimately strike the stop 60 and cause stretching of the film to the required length to effect registration.

If the eye mark 34 is considerably out of position when the automatic registration equipment is activated, there will be no excessive stretching of the film 14. This is because switch 38 is held closed by .cam 40 for a major portion of the machine cycle so as to prevent drop-out of the relay 44 if the eye mark is sensed during that portion of the cycle. Ultimately the eye mark will be sensed while switch 38 is open, and this will stop the upward movement of the dancer before it reaches its top position. Thereafter, the range of motion of the dancer will move down a small amount each cycle, as described above, until the stretching function is properly performed each cycle.

I claim:

1. Apparatus for making packages bearing indicia alinged with each package, said apparatus comprising: a plurality of uniformly-spaced receiving elements arranged to receive thin plastic film to be formed into packages, said receiving elements being arranged serially and adapted to be disposed in the configuration of an endless 100p for simultaneous movement around a closed path passing at least one packaging station; means to support a supply of stretchable film carrying repetitive indicia having a repeat spacing slightly less than the spacing between said receiving elements; film advancing means to feed said film from said film supply to said receiving elements to be applied thereto and formed into packages; package-forming means at one of said stations and operable with each of said receiving elements in sequence on a cyclical schedule synchronized with the arrival of said receiving elements at said one packaging station; means for activating said film advancing means at some time during each cycle of operation of said package-forming means; control means including sensing means responsive to the indicia on a part of said film between said advancing means and said film supply, said control means being operative to deactivate said advancing means each time one of said indicia is detected by said sensing means, said advancing means furnishing to said receiving elements during each cycle an amount of film equal to one repeat of said indicia and .the movement of said elements from one position to the next stretching said amount of film to a length corresponding to the spacing between said elements, whereby to maintain said indicia in alignment with said elements.

2. Apparatus for making packages bearing indicia aligned with each package, said apparatus comprising: a plurality of uniformly-spaced receiving elements arranged to receive thin plastic film tobe formed into packages, said receiving elements being arranged serially and adapted to be disposed in the configuration of an endless loop for simultaneous movement around a closed path passing at least one packaging station; drive means for moving said receiving elements with a cyclical intermittent indexing motion; means to support a supply of stretchable film carrying repetitive indicia having a repeat spacing slightly less than the spacing between said receiving elements; film advancing means to feed said film from said film supply to said receiving elements to be applied thereto and formed into packages; package-forming means at one of said stations and cyclically operable with each of said receiving elements in sequence while the receiving elements are at rest between indexing movements; means for activating said film advancing means at some time during each cycle of said drive means; control means including sensing means responsive to the indicia on a part of said film between said advancing means and said film supply, said control means being operative to deactivate said advancing means each time one of said indicia is detected by said sensing means, said advancing means furnishing to said receiving elements during each cycle of said drive means a predetermined amount of film equal to one repeat of said indicia the indexing movement of said elements from one position to the next stretching said amount of film to a length cor-responding to the spacing between said elements, whereby to maintain said indicia in alignment with said elements.

3. Apparatus for making packages bearing indicia aligned with each package, said apparatus comprising: a plurality of uniformlyspaced receiving elements arranged to receive thin plastic film to be formed into packages, said receiving elements being arranged serially and mounted for simultaneous movement around a closed path passing at least one packaging station; drive means for moving said receiving elements with a cyclical intermittent indexing motion; means to support a supply of stretchable film carrying repetitive indicia having a repeat spacing slightly less than the spacing between said receiving elements; film advancing means to feed said film from said film supply to said receiving elements to be applied thereto and formed into packages; spring-loaded slack take-up means engaged with said film between said advancing means and said elements; stop means to arrest the movement of said take-up means towards said elements; package-forming means at one of said stations and cyclically operable with each of said receiving elements in sequence While the receiving elements are at rest between indexing movements; means for activating said film advancing means at some time during each cycle of said drive means; control means including sensing means responsive to the indicia on a part of said film between said advancing means and said film supply, said control means being operative to deactivate said advancing means and arrest the film movement each time one of said indicia is detected by said sensing means, said advancing means furnishing to said receiving elements during each cycle of said drive means an amount of film equal to one repeat of said indicia, the indexing movement of said elements from one position to the next causing said takeup means to strike said stop means and thereby limit the drawing of said film so as to stretch said amount of film to a length corresponding to the spacing between said elements, whereby to maintain said indicia in alignment with said elements.

4. Apparatus for making packages bearing indicia aligned with each package, said apparatus comprising: a

plurality of uniformly-spaced receiving elements arranged spacing slightly less than the spacing between said receiving elements; a set of power-operated draw rolls to feed said film from said supply to said receiving elements to be applied thereto and formed into packages; a springloaded dancer roll engaged with said film between said draw rolls and said elements to take up the film slack and maintain a relatively moderate tension therein, said dancer roll being mounted for movement towards and away from said elements; stop means to arrest the movement of said dancer roll towards said elements; packageforming means at one of said stations and cyclically operable with each of said receiving elements in sequence while the receiving elements are at rest between indexing movements; means for activating said draw rolls at some time during each cycle of said drive means; control means including photocell means responsive to the indicia on a part of said film between said draw rolls and said film supply, said control means being operative to deactivate said draw rolls and arrest the film movement each time one of said indicia is detected by said photocell sensing means, said draw rolls furnishing to said receiving elements during each cycle of said drive means an amount of film equal to one repeat of said indicia, the indexing movement of said elements from one position to the next causing said dancer roll to strike said stop means and thereby limit the drawing of said film so as to stretch said amount of film to a length corresponding to the spacing between said elements, whereby to maintain said indicia in alignment with said elements.

5. The method of registering repetitive indicia on a web of material with uniformly-spaced elements to which said material is to be applied and which are moving sequentially through a series of operating positions, the repeat spacing of said indicia initially being less than the element spacing; said method comprising the following steps, not necessarily in the order recited: advancing said material towards said elements, stopping the advancing movement of said material when a portion of material equal to one repeat of said indicia has been advanced, and stretching said advanced portion of material to a dimension corresponding exactly to the spacing between said elements, thereby to maintain alignment between said indicia and said elements.

6. The method of registering repetitive indicia on a web of material with uniformly-spaced elements to which said material is to be applied and which are moving sequentially through a series of operating positions, the repeat spacing of said indicia initially being less than the element spacing; said method comprising the following steps, not necessarily in the order recited: applying said web to said elements, advancing said web towards said elements, stopping the advancing movement of said web when a portion of material equal to one repeat of said indicia has been advanced, and stretching said advanced porttion of material by tension created from the movement of said elements from one of said positions to the next position so as to extend said advanced portion to a dimension corresponding exactly to the spacing between said elements, thereby to maintain alignment between said indicia and said elements.

7. The method of registering repetitive indicia on a web of material with uniformly-spaced elements to which said material is to be applied and which are moving sequentially through a series of operating positions, the repeat spacing of said indicia initially being less than the element spacing; said method comprising the following steps, not necessarily in the order recited: applying said Web to one of said elements, advancing said material towards said elements, stopping the advancing movement of said material when a portion of material equal to one repeat of said indicia has been advanced, stretching said advanced portion of said material under relatively high tension to a dimension corresponding exactly to the spacing between said elements, relaxing the stress in the stretched portion to a relatively low tension, and applying said relaxed stretched portion to the next one of said elements in the sequence with the indicia maintained in alignment with the elements respectively.

8. The method of registering repetitive indicia on a web of material with uniformly-spaced elements to which said material is to be applied and which are to be moved sequentially and intermittently in a cyclical pattern through a series of operating positions, and wherein the repeat spacing of said indicia on the web in its original form is less than the element spacing; said method comprising the following steps carried out during each cycle of movement of the elements; applying said web to said elements by movably-mounted spring-loaded slack take-up means; starting an indexing movement of the elements, thereby pulling said web, and said slack take-up means towards said elements; starting the feeding of said web towards said slack take-up means; arresting the movement of said slack take-up means before the end of said indexing motion; stretching the advanced portion of material by tension created from the continued movement of said elements while said take-up means is arrested; stopping the indexing movement of said elements when the next operating position thereof is reached; and stopping the feeding of said web when a portion of material equal to one repeat of said indicia has been advanced, each such advanced portion of web being stretched to a dimension corresponding exactly to the spacing between said elements so as to maintain alignment between said indicia and said elements.

9. The method of registering repetitive indicia on a web of material with uniformly-spaced elements to which said material is to be applied and which are to be moved sequentially and intermittently in a cyclical pattern through a series of operating positions, and wherein the repeat spacing of said indicia on the web in its original form is less than the element spacing; said method comprising the following steps carried out during each cycle of movement of the elements; starting the feeding of said web towards said elements; stretching the portion of material fed towards said element by tension created from indexing movement of said elements at a speed greater than the feed rate of the web; stopping the indexing movement of said elements when the nextoperating position thereof is reached; and stopping the feeding of said web when a portion of material equal to one repeat of said indicia has been advanced, each such advanced portion of web being stretched by said tension to a dimension corresponding exactly to the spacing between said elements so as to maintain alignment between said indicia and said elements.

10. The method of registering repetitive indicia on 'a web of'material with uniformly-spaced elements to which said material is to be applied and which are to be moved sequentially and intermittently in a cyclical pattern through a series of operating positions, and wherein the repeat spacing of said indicia on the web in its original form is less than the element spacing; said method comprising the following steps carried out during each cycle of movement of the elements; starting the feeding of said web towards said elements; stretching the portion of material fed towards said elements by increased tension created from indexing movement of said elements at a speed greater than the feed rate of the web; lowering the speed of indexing movement to below the feed rate of said web so as to reduce the tension as the end of the indexing movement is approached; stopping the indexing movement of said elements when the next operating position thereof is reached; stopping the feeding of said web when a portion of material equal to one repeat of said indicia has been advanced, each such advanced portion of web being stretched by said tension to a dimension corresponding exactly to the spacing between said elements so as to maintain alignment between said indicia and said elements.

11. Apparatus for applying a web bearing repetitive indicia to respective uniformly-spaced receiving elements arranged serially and mounted for simultaneous movement around a closed path; drive means for moving said receiving elements with a cyclical intermittent indexing motion, said drive means being operable to accelerate the elements to a relatively high speed and to decelerate said elements at the end of each indexing cycle through a range of lower speeds; power-operated means to feed said web to said receiving elements to be applied thereto, said power-operated means being arranged to feed said Web at a speed less than said relatively high speed of said receiving elements; movable slack take-up means engaged with said web between said power-operated means and said elements to take up the web slack and maintain a relatively moderate tension therein; stop means to arrest the movement of said slack take-up means at a predetermined position during indexing of said elements; means for activating said power-operated means while said elements are being indexed and for maintaining such activation at least until the end of the indexing movement has been reached; control means responsive to the indicia on a part of said web preceding said power-operated means, said control means being operative to deactivate said power-operated means each time one of said indicia is detected, thereby furnishing to said receiving elements during each cycle of said drive means an amount of said web equal to one repeat of said indicia, the indexing movement of said elements at said relatively high speed causing said slack take-up means to engage said stop means and thereby limit the drawing of said web due to the relatively lower speed of Web feed by said poweroperated means, thereby to stretch said amount of film to a length corresponding to the spacing between said elements, the deceleration of said elements near the end of the indexing movement serving to relax the tension in the web as the element speed drops below the web feed speed.

12. Apparatus for applying a web bearing repetitive indicia to respective uniformly-spaced receiving elements arranged serially and mounted for simultaneous movement around a closed path; drive means for moving said receiving elements with a cyclical intermittent indexing motion, said drive means being operable to accelerate the elements to a relatively high speed and to decelerate said elements at the end of each indexing cycle through a range of lower speeds; said elements remaining stationary in a rest period between indexing movements; power-operated means to feed said web to said receiving elements to be applied thereto, said power-operated means being arranged to feed said web at a speed less than said relatively high speed of said receiving elements; means for activating said power-operated means while said elements are being indexed and for maintaining such activation at least until the end of the indexing movement has been reached; means operable during indexing of said elements to restrain the transfer of said web to said elements to a speed no greater than the feed rate of said power-operated means, thereby to etfect stretching of the Web as the elements continue their indexing movement, the deceleration of said elements near the end of the indexing movement serving to relax the tension in the web when the element speed drops below the web feed speed; and control means responsive to the indicia on a part of said Web preceding said power-operated means, said control means being operative to deactivate said power-operated means each time one of said indicia is detected, thereby assuring that said receiving elements are furnished during each cycle of said drive means an amount of said Web equal to one repeat of said indicia.

13. Apparatus for applying a web bearing repetitive indicia to respective uniformly-spaced receiving elements arranged serially and mounted for simultaneous movement around a closed path; drive means for moving said receiving elements with a cyclical intermittent indexing motion; power-operated means to feed said web to said receiving elements to be applied thereto; movable slack take-up means engaged with said Web between said poweroperated means and said elements to take up the web slack and maintain a relatively moderate tension therein; stop means to arrest the movement of said slack take-up means at a predetermined position during indexing of said elements, thereby to limit the speed of web feed to that of said power-operated means; means for activating said power-operated means while said elements are being indexed and for maintaining such activation at least until the end of the indexing movement has been reached; control means responsive to the indicia on a part of said web preceding said power-operated means, said control means being operative to deactivate said power-operated means each time one of said indicia is detected, thereby furnishing to said receiving elements during each cycle of said drive means an amount of said web equal to one repeat of said indicia, said amount of film being stretched to a length corresponding to the spacing between said elements by the indexing movement of said elements; and means operable near the end of the indexing movement to relax the tension in the web by causing the web feed speed to exceed the element speed.

14. The method of registering repetitive indicia on a Web of material with uniformly-spaced elements to which said material is to be applied and which are to be moved sequentially and intermittently in a cyclical pattern through a series of operating positions, and wherein the repeat spacing of said indicia on the web in its original form is less than the element spacing; said method comprising the following steps carried out during each cycle of movement of the element; starting the feeding of said web towards said elements; stretching the portion of material fed towards said elements by increased tension created from indexing movement of said elements at a speed greater than the feed rate of the web; altering the ratio of the speed of indexing movement with resepct to the feed rate of said web so as to reduce the web tension at the end of the indexing movement; and stopping the feeding of said web when a portion of material equal to one repeat of said indicia has been advanced, each such advanced portion of web being stretched by said tension to a dimension corresponding exactly to the spacing between said elements so as to maintain alignment between said indicia and said elements.

References Cited UNITED STATES PATENTS 2,259,302 10/1941 Evans 5351 3,294,301 12/1966 Richter 535l XR WILLIAM W. DYER JR., Primary Examiner. R. ALVEY, Assistant Examiner. 

